How LED Lights are Saving Fishes’ Lives

Bycatch – the unwanted fish, dolphins, whales and birds that get caught in longlines, gillnets and trawlers that are discarded.

40% of the catch is bycatch, which means that it can result in over-fishing, reducing populations of potentially endangered fish, and interrupts food chains and damages ecosystems.

When the Norwegian coast guard filmed a Scottish fishing vessel dumping 5 tons of dead fish back in to the North Sea six years ago, the conversation turned to the complex EU rules and fishing quotas. Over one million tons of dead fish are dumped back into the North Sea every year because catches exceed the EU fishing quotas.

So, when this problem reached the ears of Dan Watson, he began work on SafetyNet. An ocean fishing net that allows certain fish to escape via lighted rigs, SafetyNet allows more catch selectivity. “There can be no villains, there can be no victims, there are just problems,” Watson says. “I started this project because I wanted to go some way towards solving that problem.”

Designed to free young and endangered fish, the SafetyNet works by using fitted LED rings which flash to alert smaller fish. They can then escape by squeezing through the rings. However, this does depend on the type of fish that you’re trying to catch, and so each new piece of gear responds to a different species and their size, shape and behavior. The more we know about the ways we can stop different things being caught, the more we can make bespoke nets,” Watson says.

In 2011, designers hacked LED fishing lights ordinarily used to attract fish and re-purposed them to drive turtles away. Globally, thousands of turtles die each year because they are trapped and drowned by dense gillnets. LED lights are tuned to a certain wavelength that turtles can see, they recognise the nets as barriers and avoid them. Through this, they’ve reduced bycatch by up to 60% during trials in Mexico, Peru and Indonesia, and are now working with US fisheries too.

Ultraviolet light work in a similar way to steer hammerhead sharks away too.